Question: Should I go to the emergency room when I have a high, persistent fever?
Answer: What I would say as far as making that decision to go to the emergency department is that if you have a persistent, high fever that you think is leading to dehydration, if you have trouble breathing, if someone comments that you're looking rather blue in color or that you're breathing rapidly. If you're having chest pain or belly pain, or if someone notes that you seem to be confused, more lethargic -- in kids if they are fussy and irritable and not quite acting themselves. If you have a seizure or other form of convulsion, then those are times that I would consider going to the emergency department. Those suggest some more serious complications of the flu or that something else might be going on.
Also, if you've had flu-type symptoms and they seem to get better, but then a few days later you start to develop a high fever and a cough again, then that would be an indication to seek medical attention, because you're more likely to have now what's called a secondary infection -- so a bacterial infection that is caused because of the initial flu.